Piston-ring burr-removing device



Nov. 25, 1930. ERN i,'783,12l

PISTON RING BURR REMOVING DEVICE Filed Nov. 23, 1929 2 Sheets-$hegt l INVENTOR dose ff. weer-72,-

ATTORNEYS.

' PISTON RING BURR REMOVING DEVICE Filed Nov. 23, 1929 2 Sheets-Sheet 2 53 be H INVENTOR 9 058??? J1. f/oerlz.

TTORNEYQS.

Patented Nov. 25, 1930 JOSEPH 1r. nonaiv, or 'saemaw,

TION, A CORPORATION OF MICHIGAN MICHIGAN, ASSIGNOR T W'ILCOX-BICH CORPORA- PISTON -BIN G BURR-REMOVING DEVICE Application filed November 23, 1929. Serial No. 409,398.

This invention relates to improvements in trimming devices for surface grinding machines.

The main objects of this invention are to provide an improved device particularly suitable for removing burrs from piston rings during the grinding operation; to provide aburr removing device which is automatically operable during the grinding operation; and to provide an apparatus of simple construction which can be readily attached to the usual piston ring grinding machine and which will efliciently trim the burrs from the inner edges of the rings as they are being ground.

. An illustrative embodiment of this invention is shown in the accompanying drawings, in which Fig. 1 is a view in side elevation of a sur- :0 face grinding machine equipped with my improved device.

Fig. 2 is an enlarged plan view of the work "1101 ing mechanism, conveyor and trimming device with the grinding wheel shown in po- 25 sition thereabove.

Fig. 3 is a view in side elevation of the same. ig. 4 is a sectional view taken on the line 4-4 of Fig. 3.

Fig. 5 is an enlarged fragmentary Ian .30 View showing the cutting end of the urr trimming device in engagement with the piston ring.

' Fig. 6 is a fragmentary. sectional view taken on the line 6-6 of Fig. 5.

Fig. 7 is an enlarged view in perspective of the cam which controls the cutting head of the burr trimming tool.

Hcretofore on piston ring grinding machines in which the burr removing or trimming tool is controlled by the grinding head, much trouble has been experienced by the tool being moved into engagement with the ring before the ring has been moved into .proper position. The result is that the tip end of the trimming tool contacts with and rides over the top side of the ring and scores its surface. This scorin 4 results in an av erage of 7% of the rings icing rejected after grinding. About 5% of these rejected rings can be reclaimed by regrinding but the halclosely adjacent anee are scored too deeply to remedy and improper action of tool actuating mechanism and sometimes by the ring conveyor and holder getting slightly out of timed relation with the reciprocation of the grinding head.

In my present invention these difliculties have been entirely overcome as it is impossible for the tool to engage the ring until the ring is in proper position.

In the construction shown in the drawings a surface grinding machine 8, having a reciprocable carriage 9 which carries a grinding wheel 10, ism-provided with a vertically disposed framework 11 which serves as a magazine for holding a su ply ofpiston rings 12. Means are provided for moving the rings 12 into position to be worked on by the grinding wheel 10 and comprise a conveyor in the form of a horizontally disposed annular plate 13, of less thickness than the rings 12, mountedon the top end of a ver tically disposed shaft 14 which is rotatable to revolve the plate 13 in a horizontal plane.

The magazine 11 is open at the top and bottom and the lower end thereof is disposed plate 13. A plurality of circular openings 15 of slightly greater diameter than the rings 12, are provided in the conveyor 13. The openings are disposed with respect to the lower end of the magazine 11 so that piston rings 12 will drop thereinto by gravity when in registry therewith. A support 16 is rovided underneath the conveyor 13 in sli ing contact therewith for supporting the pieces of work when fed thereinto from the magazine 11 and while they are being moved from the magazine to a position beneath the grinding wheel 10. A revolving magnetic head 17, of substantially the same size as the piston rings 12, is provided immediately beneath.

the grinding wheel 10 in the usual manner for magnetically engaging the rings and spinning'them during the grinding operation.

The improved means for trimmingthe inner upper edge of the ring during the grinding operation comprises a bracket arm 18 rigidly to the top surface of the secured at one end by studs 19 to the base plate 20 of the magazine. The outer free end of the bracket 18 has one end of an elongated spring arm 21 secured thereto, the other end of which is provided with a transversely disposed downwardly inclined finger 22. The tip end of the finger 22 is provided with a depending cutter 23, positioned so as to normally yieldingly engage the inner upper edge of a piston ring when in grinding position on the head 17.

Means is provided for raising the free end of the spring arm 21 and cutter carried thereby from engagement with the work and comprises a cam 24 in the form of an upstanding annular rim concentrically mounted on the top surface of the conveyor 13. The top rim 27 of the cam 24 is provided with a plurality of notches 25 which are adapted to receive the spring arm 21 therein and when in such position permitthe cutter to engage the piston rin The conveyor 13 is rotated clockwise, in the illustrated instance and the rear end of each of the notches 25 terminates in an inclined surface 26, which upon. rotation of the conveyor and cam 24, is adapted to engage the spring arm 21 and raise the cutter 23 from engagement with the work. i

In the operation of this machine a number of piston rings 12 are loaded in the magazine 11 from the top thereof and the grinding machine operated in the usual manner, whereby the carriage 9 moves forward at the same time that the grinding wheel 10 is rotated. Upon rotation of the conveyor 13, a piston ring from the magazine will drop into the opening 15 when moved in registry beneath the open bottom of the magazine. Upon another rotation of the conveyor 13 of one-- fourth of a turn, the piston ring is slid on its support 16 to a position beneath the grinding wheel 10 and on to the magnetic head 17 which is actuated to spin the ring during the grinding thereof. During the rotation of the conveyor 13 the spring arm 21 rides up the inclined cam surface 26 and is retained in raised position on the rim 27 until the piston ring is in position on the head 17, at which time the spring arm comes in registry with the notch 25 and snaps down thereinto, thus bringing the cutter 23 into yielding operative engagement with the upper inner edge of the ring.

As the ring is spun around by the head 17 during the grinding of the top surface thereof by the wheel 10, the cutter 23 will effectively trim off and remove any burrs which are caused by the grinding wheel. Atthe end of the grinding operation the conveyor 13 is again rotated one-fourth of a turn to bring another piece of work into position to be operated upon by the grinding wheel. At initial movement of the conveyor the spring arm 21 will ride up the inclined surface 26 of the notch 25 in which it is embraced, thus lifting the cutter 23 out of engagement with the finished ring, and maintain it in such raised position until the new piece of work has been deposited upon the magnetic head 17. \Nhen this has been accomplished the arm 21 will again snap down into a notch 25 which is in registry therewith and thus again permit the cutter 23 to be in effective operative position with respect to such new piece of work.

Although but one specific embodiment of this invention has been herein shown and described, it will be understood that numerous details of the construction shown may be altered or omitted without departing from the spirit of this invention as defined by the following claims.

I claim:

1. The combination of a surface grinding machine having a grinding wheel, a work holder, means providing a relative feeding movement between the work holder and wheel, a tool for engaging the work when in grinding position, and means operable by said work holder for controlling movement of said tool, to lift the same during such feeding movement.

The combination of a surface grinding machine having a work holder and grinding wheel, means providing a relative feeding movement between the work and wheel, a tool mounted to normally operatively engage the work in said holder during the grinding operation, and means operable during said feeding movement for rendering said tool inoperative by lifting the same from said work.

3. The combination of a surface grinding machine having a work holder and grinding wheel, means providing a relative feeding movement between the work and wheel, a tool normally yieldingly urged into operative engagement with the work in said holder during the grinding operation and up\ *ardly acting cam means operable during said feeding movement for retracting said tool to inoperative position.

1. The combination of a surface grinding machine having a work holder and grinding wheel, means providing a relative feeding movement between the work and wheel, a tool mounted to normally operatively engage the work in said holder during the grinding operation, and means controlled by said feeding movement for rendering said tool inoperative.

5. The combination of a surface grinding machine having a work holder and grinding wheel, means providing a relative feeding movement between the work and wheel, a tool normally yieldingly urged into operative engagement with the work in said holder during the grinding operation, and means actuated by the feeding movement of said work holder for retracting said tool to inoperative position.

6. The combination of a surface grinding machine having a work holder and grinding wheel, means providing a relative feeding movement between the work and wheel, a tool 5 normally yieldingly urged into operative engagement with the work in said holder during the grinding operation, and a cam for moving said tool to inoperative position during the feeding movement of said work holder.

1. 7. The combination of a surface grinding machine having a work holder and grinding wheel, means providing a relative feeding movement between the work and wheel, a tool normally yieldingly urged into operative engagement with the work in said holder during the grinding operation, and a cam actuated by said work holder for movin said tool to inoperative position during the feeding movement of said work holder.

8. The combination of a surface grinding machine having a grinding wheel, a magazine for pieces of work, a conveyor for moving pieces of work from said magazine to said wheel, a tool for engaging the pieces of work whenin grinding position, and means actuated by said conveyor for controlling movement of said tool.

9. The combination of a surface grinding machine having a grinding wheel, a work 0 holder, means providing a relative feeding movement between the work and wheel, a tool for normally engaging the work when in grinding position, and means operable by said work holder for disengaging said tool from the work.

10. The combination of a surface grinding machine having a grinding wheel, a magazine for pieces of work, a conveyor for moving pieces of work from said magazine to said wheel, a tool-for trimming pieces of work when in grinding position, a spring arm supporting said tool and normally urging it into operative engagement with the work, and a cam carried on said conveyor for engaging and moving said tool to inoperative position during the feeding movement of said conveyor.

11. The combination of a surface grinding machine having a grinding wheel, a magazine 5 for pieces of work, a conveyor for moving piecesof work from said magazine to said wheel, a tool for trim'ming'pieces of work when in grinding position, a spring arm mounted on said magazine for supporting said tool and normally urging it into operative engagement with the work, and a cam carried on said conveyor for engaging and moving said tool to inoperative position during the feeding movement of said conveyor.

JOSEPH H. HOERN. 

